What is Splenomegaly?
Splenomegaly is the term used to describe a condition where the spleen grows larger than its normal size. The spleen, which is located in the upper left part of your abdomen near your ribs, plays a crucial role in blood formation and keeping your immune system functioning properly. It helps remove damaged red blood cells, platelets, white blood cells from your body, and removes bacteria and other foreign substances. The spleen also helps in the creation and storage of certain types of immune cells, called T and B lymphocytes, which are necessary for making specific proteins (immunoglobulin G or IgG) that fight off infections. The spleen also creates two important immune system peptides, properdin and tuftsin. Around one-third of the platelets in your body, which are crucial for blood clotting, are stored in the spleen.
Spleen size and weight can vary depending on your weight, height, and sex. For instance, men, as well as taller or heavier individuals, generally have larger spleens. A normal-sized spleen can be up to 12 cm long. If it’s between 12 and 20 cm, it is considered enlarged, while anything over 20 cm is significantly larger than normal. A normal adult spleen weighs between 70 g and 200 g, while a spleen weighing 400 g to 500 g is enlarged, and anything over 1000 g is significantly larger than normal.
In general, you wouldn’t be able to feel a healthy-sized spleen by touching your abdomen, but sometimes it could be felt due to variations in body size and chest structure. Physicians can detect an enlarged spleen either through a physical exam or with the help of imaging tests like ultrasound, CT scans, or MRI. Sometimes an enlarged spleen might be temporary due to a short-term illnesses, but it could also signify a serious ongoing medical condition.
What Causes Splenomegaly?
Splenomegaly is when your spleen grows larger than it should. There are many possible causes for this condition.
1. Liver diseases such as cirrhosis or hepatitis: These conditions damage the liver and increases pressure in your blood vessels, which in turn can cause the spleen to enlarge.
2. Blood cancers like lymphomas, leukemias, or myeloproliferative disorders: These diseases can cause cancerous cells to move into the spleen, causing it to swell.
3. Venous thrombosis, meaning blood clots in the portal or hepatic veins: These can also raise blood pressure in the spleen causing it to expand.
4. A congested spleen due to blood clots, portal hypertension, or heart failure.
5. Low blood cell counts due to conditions like autoimmune hemolytic anemia or immune-mediated neutropenia can also cause the spleen to grow.
6. Pediatric sickle cell disease and other blood disorders can trigger an event known as splenic sequestration, where a large number of blood cells get stuck in the spleen.
In addition, infections (like bacterial endocarditis or infectious mononucleosis) and connective tissue diseases (like lupus or rheumatoid arthritis) can also lead to splenomegaly. Other underlying conditions like glycogen storage diseases or abnormalities in the spleen like hemangiomas could be at fault too.
The specific process causing spleen expansion can vary based on the underlying condition. For instance, during an acute infection, the spleen works harder to clear the body of disease-causing antigens and creates more immune cells which can cause the organ to enlarge.
In severe cases, like in children with sickle cell disease or beta-thalassemia, a life-threatening condition known as a splenic sequestration crisis may arise. This occurs when a significant amount of blood gets trapped in the spleen. Symptoms include a sudden drop in hemoglobin, leading to a condition called ‘hypovolemic shock’ which can be fatal. Over time, these children experience multiple “hits” of damage to the spleen causing it to progressively scar and shrink. By adulthood, they typically end up with a small, scarred spleen, which is why adults rarely experience a splenic sequestration crisis.
Risk Factors and Frequency for Splenomegaly
Splenomegaly, or an enlarged spleen, is quite uncommon, affecting about 2% of people in the United States. There isn’t any particular group more likely to have it – it occurs equally among different ethnicities, genders, and ages in adults. However, in Asia and Africa, this condition is very common due to tropical diseases. One important thing to note is that older people have a higher risk of their spleen rupturing, because the protective covering of the spleen gets thinner with age.
Signs and Symptoms of Splenomegaly
Splenomegaly is a condition where the spleen becomes enlarged. Most of the time, people with splenomegaly feel a vague discomfort in their abdomen. They may also experience belly pain on the upper left side or shoulder pain. Other symptoms might include a bloated or swollen belly, loss of appetite, becoming satisfied quickly when eating, and general weakness. They may also lose weight or sweat during the night. If the splenomegaly is due to an infection, individuals may have fever, chills, fatigue, or other symptoms related to the specific infection. If the liver is affected, symptoms related to liver disease may appear. If the situation worsens, people can have symptoms related to low red blood cell count like weakness, shortness of breath, tiredness, easy bruising, abnormal bleeding, or small red spots on the skin.
Doctors check for an enlarged spleen by examining the patient while they’re lying down. Light pressure is applied to the belly area, under the left ribcage, while the person takes a deep breath. If the spleen’s edge can be felt more than 2 cm below the ribcage, it could be a sign of splenomegaly. The spleen, in severe cases, can even extend deep into the abdomen, crossing the abdomen’s midline and even reaching into the pelvis. However, in about 3% of adults, the spleen can be felt even when its size is normal.
Sometimes, splenomegaly can be detected through physical signs related to the underlying disease causing it. For instance, individuals with splenomegaly due to an infection might show signs related to the specific infection. People with blood diseases might have small red spots, abnormal bleeding from the mucous membranes, or pale color. Individuals with liver disease might have yellow skin and eyes, an enlarged liver, accumulation of fluid in the abdomen, or reddish skin markings. And those with diseases related to the immune system might show signs of joint pain, swelling, skin rashes, or abnormal lung examination results.
Testing for Splenomegaly
A combination of blood testing and medical imaging can help diagnose an enlarged spleen, also known as splenomegaly, and identify its cause. Changes in the count and shape of white blood cells (WBC), red blood cells (RBC), and platelets, which are all components of your blood, can vary depending on the underlying disease. Abnormalities in tests for liver function, pancreatic enzymes (lipase), immune system activity (rheumatologic panels), and specific infectious diseases can also assist in diagnosing the cause of the enlargement.
Hypersplenism, a condition where the spleen is overactive, might present with a reduced number of white blood cells (leukopenia), red blood cells (anemia), and platelets (thrombocytopenia).
Imaging can also help diagnose an enlarged spleen and identify its cause. On a CT scan, the spleen appears similar in density to the liver. Besides diagnosing an enlarged spleen (defined by a spleen measurement of more than 10 cm in length), an abdominal CT scan may detect abscesses in the spleen, abnormalities in the blood vessels, cysts, inflammatory changes, injury due to trauma, swollen lymph nodes in the abdomen, or abnormalities in the liver.
Ultrasound is a useful imaging method for measuring the spleen and doesn’t expose the patient to the radiation associated with a CT scan. A normal spleen size measured by ultrasound is less than 13 cm from top to bottom, 6 cm to 7 cm from the inside to the outside, and 5 cm to 6 cm from the front to the back.
In some cases, other imaging methods like MRI and PET scans, a scan that focuses on the liver and spleen, surgical removal of the spleen (splenectomy), or a biopsy of the spleen might be necessary.
Treatment Options for Splenomegaly
The treatment for splenomegaly, which is an enlarged spleen, focuses on dealing with the core problem causing the enlargement, and preventing complications due to the enlarged spleen itself. For instance, an enlarged spleen can be more likely to rupture, which is a severe health risk. Therefore, special attention should be given to protecting the patient from stomach injuries.
The treatment can vary greatly depending on the cause and the patient. For example, a young and healthy person with an enlarged spleen due to mononucleosis, which is a common viral infection, would primarily need to avoid any abdominal injuries. On the other hand, a person with a significantly enlarged spleen due to a type of cancer known as hairy cell leukemia might need to have their spleen removed in an operation known as a splenectomy. What happens next largely depends on the specific health problem causing the enlarged spleen.
Splenic sequestration, which is a condition where a lot of blood gets trapped in the spleen, is sometimes observed in individuals with sickle cell anemia, a genetic blood disorder. This condition can often be managed with blood transfusions. Sometimes, a splenectomy might be necessary for a condition known as ITP, where the body’s immune system mistakenly attacks platelets, which are cells that help the blood to clot. Low dose radiation therapy can also help to reduce the size of the spleen in patients with primary myelofibrosis, a rare bone marrow disorder.
Patients who undergo a splenectomy are more likely to develop infections due to certain types of bacteria, such as Haemophilus Influenzae, Streptococcus pneumoniae, and Neisseria meningitidis. Vaccinations against these bacteria are highly recommended for patients who have had their spleens removed. It’s important to pay careful attention to such patients if they develop a fever, as they might require an intensive course of antibiotics to kickstart the body’s fight against an infection.
What else can Splenomegaly be?
Splenomegaly, the medical term for an enlarged spleen, can be caused by several different conditions, often requiring a careful and detailed examination to identify the root cause. Some of these potential causes include:
- Cirrhosis (liver scarring)
- Hepatitis (liver inflammation)
- Rheumatoid arthritis (a chronic inflammatory disorder affecting the joints)
- Felty Syndrome (rare complication of rheumatoid arthritis)
- Systemic Lupus Erythematosus (an autoimmune disease that affects many parts of the body)
- Lymphoma (cancer of the lymphatic system)
- Sickle cell anemia (a genetic disorder that affects red blood cells)
Liver diseases such as cirrhosis and hepatitis are common causes. To diagnose these conditions, doctors might look for signs of liver disease, check for abnormal liver functions, and use imaging tests to study the liver.
Splenomegaly can also be seen in cases of blood cancers or in the presence of other tumors. Presence of general illness symptoms and weight loss might hint towards these causes. In these cases, a blood test and biopsy could be helpful for diagnosis.
Autoimmune diseases like Rheumatoid Arthritis and Systemic Lupus Erythematosus often come with the symptom of an enlarged spleen. In Rheumatoid Arthritis patients, the combination of an enlarged spleen and a low white blood cell count is known as Felty Syndrome.
Viruses, bacteria, fungi and certain bacterial infections can also cause splenomegaly and should be ruled out as potential causes. In addition, complete blood tests, along with examinations of red blood cells, can help in identifying diseases where the spleen is abnormally holding back blood cells.
Rare diseases that cause build-ups of substances, such as Glycogen Storage Diseases, can enlarge the spleen and should be considered when more common causes have been ruled out. These disorders usually present with other specific symptoms.
What to expect with Splenomegaly
The outlook for patients with splenomegaly, or an enlarged spleen, largely depends on the specific medical condition causing the enlargement. It’s important to know that regardless of the root cause, there’s indeed a high risk of the spleen rupturing, even due to minor injuries, in patients with an enlarged spleen.
Possible Complications When Diagnosed with Splenomegaly
The main concern with an enlarged spleen (splenomegaly) is that it might rupture. This is why individuals with this condition are usually told to avoid sports with a lot of physical contact or the potential for heavy impact, to help prevent this from happening. Additionally, an enlarged spleen can lead to low counts of certain cells in your blood (cytopenias). If required, removing the spleen (splenectomy) can potentially minimize these risks.
Potential Risks:
- Splenic rupture (rupture of the spleen)
- Cytopenias (reduced count of certain blood cells)
Preventative Measures:
- Avoidance of high-impact or contact sports
- Potential splenectomy (removal of the spleen) if necessary
Preventing Splenomegaly
If a patient has an enlarged spleen, they should steer clear of sports or activities that involve a lot of physical contact or have a high risk of injury. This is to prevent their spleen from accidentally bursting, which could lead to serious complications.
Once a patient has had surgery to remove their spleen (known as a splenectomy), they should be made aware of their increased vulnerability to infections. The patient should get proper immunizations to help lower this risk.
